Photographic developing compositions



Unit

2,7 53,265 PHOTOGRAPl-HC DEVELOPING COMPOSITIONS John David Kendall and Anthony Joseph Axford, Ilford, England, assignors to Ilford Limited, Ilford, England, a British company No Drawing. Application August 15, 1955, Serial No. 528,547

Claims priority, application Great Britain August 24, 1954 15 Claims. (Cl. 95-88) where R1, R2 and R3 are the same or dififerent and are hydrogen atoms or hydrocarbon groups, for instance alkyl groups, e. g. methyl, ethyl, propyl, isopropyl, or higher alkyl groups, aryl groups, e. g. phenyl or naphthyl groups, or aralkyl groups, e. g. benzyl groups. Such hydrocarbon substituent groups may themselves be substituted; for example, aryl groups may contain hydroxy, alkoxy, aryloxy, oxyalkyl, amino, substituted amino, sulphonic, carboxylic or halogen substituents.

Further, corresponding compounds in which the hydrogen atom in the 4-position of the foregoing formula is substituted by a hydrocarbon group, e. g. the 4.4-dialkyl compounds, have comparable developing activity.

The said specification proposes, inter alia, the formulation of developers containing hydroquinone or pyrogallic acid, which are themselves effective developing agents, in addition to the 3-pyrazolidone.

It has now been discovered that while photographic glycine, i. e. p-hydroxyphenyl amino acetic acid, has in itself only very Weak or negligible developing properties at pH 9 to 10 (which is typical of fine grain developers), except on prolonged development time, and the 3-pyrazolidones alone have but weak developing properties at the same pH values, the tWo may be employed together to give developing compositions of excellent quality and having important advantages.

According to the present invention, therefore, a developing composition comprises, in alkaline solution (and preferably weakly alkaline solution), p-hydroxyphenyl amino acetic acid and a 3-pyrazolidone. The remarkable results obtained are ascribed to the effect of the 3-pyrazolidone in activating the p-hydroxyphenyl amino acetic acid.

While the broad class of 3-pyrazolidones referred to above are generally useful, the preferred 3-pyrazolidones are the l-aryl-B-pyrazolidones, and particularly the l-phenyl-3-pyrazolidones, which are unsubstituted or substituted only by alkyl groups in the 4- and -positions. Specific 3-pyrazolidones of value are:

States Patent 0 2,753,265 Patented July 3, 1956 2 l-phenyl-3-pyrazolidone 1-phenyl-4-methyl-3-pyrazolidone l-phenyl-4-ethyl-3-pyrazolidone 1-phenyl-5-methyl-3-pyrazolidone 1phenyl-4.4-dimethyl-3-pyrazolidone The developing compositions according to this invention alford fine grain images of relatively soft gradation and excellent photographic quality. They may be formulated as highly concentrated solutions adapted to be considerably diluted by the user to obtain solutions of working strength.

The following examples will serve to illustrate the invention:

EXAMPLE 1 Developer composition G. p-Hydroxyphenyl amino acetic acid -c 5 l-phenyl-B-pyrazolidone 0.2 Sodium sulphite (anhydrous) 9O Borax l 2 Sodium carbonate (anhydrous) 2 Water to make 1 litre.

EXAMPLE 2 The developer composition of Example 1 was modified by using, instead of 1-phenyl-3-pyrazolidlone, 0.2 g. of l-phenyl4-methyl-3-pyrazolidone or 0.3 g. of l-phenyl- 4.4-dimethyl-3-pyrazolidone, and each gave very similar results.

in the development of a F. for 12 minutes, it yields and of very fine grain. It

EXAMPLE 3 Concentrated developer Potassium sulphite solution 71% w./v ml 422 p-Hydroxyphenyl amino acetic acid g 40 l-phenyl-3-pyrazolidone g 2 Water to make 1 litre.

To this solution was added solid caustic soda in quantity sufficient (usually about 13 g.) to bring the solution, after dilution with 9 parts of water, to a pH of 9.1.

In use, this developer is diluted with 9 volumes of water and applied to exposed photographic fast panchromatic film for 10 minutes at 68 F. A fine grain image of gamma about 0.6 is obtained. The developer has a high photographic speed. If the l-phenyl-3-pyrazolidone is omitted a negligible image is obtained even after 30 minutes at 68 F.

It r r 1ay be observed that a comparable concentrated solution using metol (p-methylamino phenol sulphate) instead of the 3-pyrazolidone cannot be formulated because, to achieve similar photographic results, 1520 g. of p-methylamino phenol sulphate are required and such a quantity would not remain in the concentrated solution.

The foregoing developer, when diluted as indicated, can be kept in full stoppered bottles for three or more months without any substantial loss of developing activity.

EXAMPLE 4 Potassium sulphite solution 74.3% w./v ml 400 p-I-Iydroxyphenyl amino acetic acid g 50 1-phenyl-3-pyrazolidone g 1.75 Potassium bromide g 8 Water to make 1 litre.

carbonates or hydroxides, alkali metal, ammonium and P alkylolamine sulphites, sodium and potassium metabisulphites, alkali metal bromides, benzotriazole, mercapto triazole and borax.

What we claim is:

1. A photographic developing composition which comprises an alkaline solution containing p-hydroxyphenyl amino acetic acid and a 3-pyrazolidone.

2. A photographic developing composition which comprises an alkaline solution at pH 9 to 10 containing p-hydroxyphenyl amino acetic acid and a 3-pyrazolidone.

3. A photographic developing composition Which comprises an alkaline solution containing p-hydroxyphenyl amino acetic acid and 1-pheny1-3-pyrazolidone.

4. A photographic developing composition which comprises an alkaline solution at pH 9 to 10 containing p-hydroxyphenyl amino acetic acid and 1-phenyl-3-pyrazo1idone.

5. A photographic developing composition which comprises an alkaline solution containing p-hydroxyphenyl amino acetic acid and a 3-pyrazolidone, said solution further containing an alkali metal carbonate.

6. A photographic developing composition Which comprises an alkaline solution at pH 9 to 10 containing p-hydroxyphenyl amino acetic acid and 1-pheny1-3-pyrazolidone, said solution further containing an alkali metal carbonate.

7. A photographic developing composition which comprises an alkaline solution containing p-hydroxyphenyl amino acetic acid and a 3-pyrazolidone, said solution further containing an alkali sulphite.

8. A photographic developing composition which comprises an alkaline solution at pH 9 to 10 containing p-hydroxyphenyl amino acetic acid and 1-phenyl-3-pyrazolidone, said solution further containing an alkali sulphite.

9. A photographic developing composition which comprises an alkaline solution containing p-hydroxyphenyl amino acetic acid and a 3-pyrazolidone, said solution containing alkali metabisulphite.

10. A photographic developing composition which comprises an alkaline solution at pH 9 to 10 containing p-hydroxyphenyl amino acetic acid and 1-pheny1-3-pyrazolidone, said solution containing alkali metabisulphite.

11. A photographic developing composition which comprises an alkaline solution containing p-hydroxyphenyl amino acetic acid and a 3-pyrazolidone, said solution containing an alkali metal bromide.

12. A photographic developing composition which comprises an alkaline solution at pH 9 to 10 containing p-hydroxyphenyl amino acetic acid and l-phenyl-B-pyrazolidone, said solution containing an alkali metal bromide.

13. A photographic developing composition which comprises an alkaline solution at pH 9 to 10 containing p-hydroxyphenyl amino acetic acid, 1phenyl-3-pyrazolidone, alkali sulphite and alkali carbonate.

14. A photographic developing composition which comprises an alkaline solution at pH 9 to 10 containing p-hydroxyphenyl amino acetic acid, lphenyl-3-pyrazolidone, alkali sulphite, alkali hydroxide and potassium bromide.

15. A photographic developing composition which comprises the following ingredients substantially in the quantities stated:

G. Potassium sulphite 297 p-Hydroxyphenyl amino acetic acid 50 1-phenyl-3-pyrazolidone 1.75 Potassium bromide 8 Water to make 1 litre.

together With sufficient potassium hydroxide to bring the pH of the said composition, when 1 part thereof is diluted with 7 parts of water, to pH 9.9.

No references cited. 

1. A PHOTOGRAPHIC DEVELOPING COMPOSITION WHICH COMPRISES AN ALKALINE SOLUTION CONTAINING P-HYDROXYPHENYL AMINO ACETIC ACID AND A 3-PYRAZOLIDONE. 